[1018] How to deal with multiple dynamic routes nuxt generate

Hey, in nuxt guide there is example how to deal with dynamic routes using promise and call to axios, now, how to deal with two of them?

generate: {
    routes: function (callback) {
      let posts = axios.get('https://api.com/posts', {params: {size: 10}}).then((res) => {
        return res.data.posts.map((post) => {
          return '/feed/' + post.id
        })
      })
      let users = axios.get('https://api.com/users', {params: {size: 10}}).then((res) => {
        return res.data.users.map((user) => {
          return '/user/' + user.id
        })
      })
      let route = Promise.all([posts, users]).then(values => {       
        return callback(null, route)
      })
    }
},

This is my example - trying to connect two promises but still have error.